The sensitivity of ultrasonography in detecting renal cortical defects in pyelonephritic patients with or without vesicoureteral reflux

The presence of renal scarring has been documented in 5% to 15% of febrile urinary tract infections. The main aim of this study was to compare the value of renal ultrasonography and cortical scintigraphy with technetium-99m dimercaptosuccinic acid (DMSA) in detecting renal cortical defects in acute pyelonephritis. Between June 2003 and February 2012 a prospective cohort study of patients aged 1 month to 14 years of age was conducted. Pediatric patients with documented urinary tract infections were evaluated with renal ultrasonography, voiding cystoureterography (VCUG) and DMSA scintigraphy. Statistical test was two-tailed and was considered significant when P≤ 0.05. The results of DMSA scans showed 70.2% of cases as being abnormal. Renal ultrasonographies were reported to be normal in 72.45 and showed mild hydronephrosis in 37.7% of cases, moderate to severe hydronephrosis in 40.62%, stone formation in 13.66% and scar formation or decreased cortical thickness in 8.2%. There was a significant difference in ultrasonography reports between patients with normal and abnormal DMSA scans (P< 0.012) but there was no significant difference in detection of scar formation between DMSA scan results and those of ultrasonography in our patients. Among patients with severe abnormalities on DMSA scintigraphy the percent of cases with vesicoureteral reflux was significantly higher than those with normal scans or mild to moderate changes on DMSA scintigraphy. (46.3% vs 26.9%). We concluded that ultrasonography is a sensitive method for detection of renal cortical defects and ultrasonography can also predict the presence of vesicoureteral reflux in pyelonephritic patients.